In a low-speed wind tunnel, the angular location(s) from the front stagnation point on a circular cylinder

Q. In a low-speed wind tunnel, the angular location(s) from the front stagnation point on a circular cylinder where the static pressure equals the free-stream static pressure, is

             (A) ± 38⁰            (B) ± 30⁰                   (C) ± 60⁰                    (D) 0⁰

Ans: ± 30⁰